Low-dose cerebral CT perfusion imaging (CTPI) of senile dementia: diagnostic performance.

To evaluate the clinical value of low-dose cerebral CTPI in the diagnosis of senile dementia, as an attempt to develop a new imaging method to diagnose this disease and measure its severity. 95 patients of senile dementia (52 with Alzheimer's disease (AD), 43 with vascular dementia (VD)) and 30 healthy subjects (control group) were underwent low-dose cerebral CTPI examinations with multi-slices spiral CT. The CTPI images were analyzed using perfusion software. Derived perfusion parameters including cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) were measured. Diagnostic value of perfusion parameters was evaluated by receiver-operating characteristic (ROC) curve. The CBV and CBF of both of frontal lobe, temporal lobe, hippocampus and basal ganglial area in the patients with senile dementia were much lower than those in the healthy group. And MTT and TTP of the areas above-mentioned in the senile dementia group were higher than those in the control group. There was statistically significant difference between them (p<0.05). The areas under ROC curves of perfusion parameters left temporal lobe MTT, left the basal ganglia MTT and left the hippocampus MTT to diagnose senile dementia were 0.959, 0.920, 0.916, and diagnostic accuracy rate is higher. The areas under ROC curve of the left frontal MTT, the left basal ganglia CBV were 0.867 and 0.819, diagnosis accuracy medium. The results showed that cerebral CTPI is valuable for the diagnosis of senile dementia.